Just for an experiment, I tried dropping the map and watch, just to see if bungie would let me do it, and sure enough, they did implement that level of detail, with a cheeky "You don't have your map, you must have dropped it somewhere." If you pick it back up, everything you explored without it will suddenly have been instantly drawn onto it. Eddings must have a godlike memory and a fast hand.
But anyway, the bug. The inventory doesn't work right after you pick them up. Trying to reorganize it moves the item you selected to places you didn't want it to go. I had to reload an old save to get it functional again.